ἀλέθω

From LSJ

γραμματική ἐστιν ἐμπειρία τῶν παρὰ ποιηταῖς τε καὶ συγγραφεῦσιν ὡς ἐπὶ τὸ πολὺ λεγομένων → grammar is a practical knowledge of the usage of poets and writers of prose

Source

Greek (Liddell-Scott)

ἀλέθω: εσα, εσμαι, έσθην, = ἀλήθω, Achmet.